Sartorial snobbery on the stage?

The recent row about Rihanna and her bra in the fields makes most classical musicians' clothing look staid, even at its shortest and tightest. 

So why do people get into such a stew over the gorgeous Yuja and her concert attire? At least she looks good in it. And as for orchestras... I'd say "don't get me started," but recently my boss at the Independent did indeed get me started, so here's the result.
http://www.independent.co.uk/arts-entertainment/music/features/why-do-critics-get-so-hot-under-the-collar-when-it-comes-to-concert-clothing-6259549.html